Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl4-induced liver fibrosis

Table 1 Detailed information on the experimental process

Modeling time	Distribution of operation	Humane	Rabbits	POW 2	POW 4	POW 6	POW 8	POW 10	Humane	Exclusion	Death	Rabbits
		Termination1	left2						Termination3			left4
0W	/	0	90	/	/	/	/	/	/	/	/	/
2W	/	0	90	/	/	/	/	/	/		/	/
4W	AAAA	0	82	AAAA	AAAA	AAA5	AA	AA	1	1	1	5
	BBBB			BBB	BBB	BBB	BBB	BBB
6W	AAAA	0	74	AAA	AAA	AAA	AA	AA	2	0	2	4
	BBBB			BBBB	BBB	BBB	BB	BB
8W	AAAA	2	64	AAA	AA	AA	AA	AA	2	0	1	4
	BBBB5			BBB	BBB	BB	BB	BB
10W	AAAA	3	53	AAA	AAA	AA	AA	AA	2	1	1	4
	BBBB			BBBB	BBB	BBB5	BB	BB
12W	AAAA	3	42	AAA	AAA	AA	AA	AA	3	0	1	4
	BBBB			BBB	BB	BB	BB	BB
14W	AAAA	2	32	AAA	AA	AA	AA	A	5	0	0	2
	BBBB5			BBB	BBB	BB	B	B
16W	AAAA	4	20	AAAA	AAA	AAA	AA	AA	4	0	1	3
	BBBB			BBB	BB	BB	BB	B
18W	AAAA	3	9	AAA	AAA	AAA	AA	AA	4	0	0	3
	BBBB5			BBB	BB	BB	B	B
20W	AAAA	2	0	AA	AA	AA	AA	A	4	1	0	2
	BBB			BBB	BBB	BB	BB5	B
Total	68	19	/	/	/	/	/	/	27	3	7	31

¹Number of rabbits with humane termination during Experiment 1;

²Number of rabbits left excluding rabbits with humane termination and failed liver stiffness measurement via ElastPQ during Experiment 1;

³Number of rabbits with humane termination during Experiment 2;

⁴Number of rabbits left excluding rabbits with humane termination, failed liver stiffness measurement via ElastPQ, and death during Experiment 2; A⁵ and B⁵ indicate rabbits with failed LSM via ElastPQ. POW: Postoperative weeks; LSM: Liver stiffness measurement; ElastPQ: Elastography point quantification; A: Rabbits receiving splenectomy and liver biopsy; B: Rabbits receiving only liver biopsy.

Table 2 Distribution of liver fibrosis stages at different time intervals in Experiment 1

	F0	F1	F2	F3	F4
0 wk	98	/	/	/	/
2 wk		/	/	/	/
4 wk		5	3	0	0
6 wk		3	4	1	0
8 wk		2	4	1	0
10 wk		1	2	3	2
12 wk		0	2	1	5
14 wk		0	1	2	4
16 wk		0	0	4	4
18 wk		0	0	3	4
20 wk		0	0	1	6
Total	8	11	16	16	25

Table 3 Basic characteristics of rabbits with different liver fibrosis stages in Experiment 1

Parameters	F0 (n = 8)	F1 (n = 11)	F2 (n = 16)	F3 (n = 16)	F4 (n = 25)
Body weight (kg)	2.34 ± 0.24	2.28 ± 0.27	2.39 ± 0.14	2.30 ± 0.38	2.24 ± 0.33
Type IV collagen (μg/L)	200.8 ± 131.5	427.1 ± 226.2	683.4 ± 332.5	1161.4 ± 482.5	1292.0 ± 689.7
Hyaluronic acid (μg/L)	225.6 ± 117.1	475.7 ± 296.4	676.2 ± 274.8	724.0 ± 264.5	1182.3 ± 1091.3
TB (μmol/L)	0.98 ± 0.53	1.91 ± 0.63	2.20 ± 0.85	1.81 ± 0.82	1.64 ± 0.91
AST (IU/L)	26.8 ± 14.7	345.0 ± 295.9	449.2 ± 304.7	666.4 ± 428.3	616.1 ± 609.2
ALT (IU/L)	14.0 ± 3.7	254.7 ± 194.0	301.5 ± 210.7	456.3 ± 316.0	486.5 ± 295.8
Albumin (g/L)	42.7 ± 4.9	40.4 ± 4.6	36.5 ± 4.3	32.3 ± 6.4	35.3 ± 5.9
LSM (kPa)	7.88 (6.60-8.46)	8.46 (6.22-10.35)	10.89 (8.09-14.46)	18.62 (16.03-21.16)	25.10 (20.28-30.95)

ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; LSM: Liver stiffness measurement; TB: Total bilirubin.

Table 4 Comparison between elastography point quantification and fibrosis blood tests

AUROC	F0-F1 vs F2-F4	F0-F2 vs F3-F4	F0-F3 vs F4
ElastPQ	0.931 (0.849-0.977)	0.969 (0.901-0.995)	0.925 (0.841-0.973)
Hyaluronic acid	0.807 (0.700-0.889)	0.677 (0.560-0.780)a	0.670 (0.553-0.774)a
Type IV collagen	0.919 (0.833-0.969)	0.861 (0.762-0.930)a	0.695 (0.578-0.795)a

Comparison of AUROC between ElastPQ and hyaluronic acid or type IV collagen,

^aP < 0.05. ElastPQ: Elastography point quantification.

Table 5 Cutoff and performance values of elastography point quantification for diagnosis of liver fibrosis stages

Parameter	F0-F1 vs F2-F4	F0-F2 vs F3-F4	F0-F3 vs F4
AUROC	0.931 (0.849-0.977)	0.969 (0.901-0.995)	0.925 (0.841-0.973)
Optimal cutoff value	11.27	14.89	18.21
Sensitivity (%)	82.5 (70.1-91.3)	87.8 (73.8-95.9)	88.0 (68.8-97.5)
Specificity (%)	94.7 (74.0-99.9)	94.3 (80.8-99.3)	84.3 (71.4-93.0)
PPV (%)	97.9 (88.9-99.9)	94.7 (82.3-99.4)	73.3 (54.1-87.7)
NPV (%)	64.3 (44.1-81.4)	86.8 (71.9-95.6)	93.5 (82.1-98.6)

PPV: Positive predictive values; NPV: Negative predictive value.

Table 6 Longitudinal changes in liver stiffness measurement (kPa) via elastography point quantification between splenectomy and sham groups

		POW 0	POW 2	POW 4	POW 6	POW 8	POW 10
F1	Group S (n = 5)	8.46 (6.63-8.50)	8.74 (6.97-8.91)	11.34 (9.13-12.89)	14.32 (11.45-15.45)	18.89 (16.43-19.23)	19.24 (17.78-21.09)
	Group L (n = 4)	8.59 (7.12-10.13)	12.79 (11.01-14.62)	14.35 (12.24-16.70)	16.30 (13.25-20.07)	21.01 (16.11-25.45)	23.34 (20.66-26.15)
F2	Group S (n = 4)	10.81 (8.34-13.48)	14.45 (12.53-15.70)	18.28 (16.72-18.56)	20.73 (18.09-22.26)	25.50 (23.10-25.89)	30.79 (27.29-33.31)
	Group L (n = 4)	10.50 (9.31-11.96)	15.39 (13.55-16.92)	17.90 (16.01-19.27)	20.25 (18.92-21.51)	23.89 (23.15-25.24)	30.60 (28.54-32.29)
F3	Group S (n = 4)	19.19 (17.77-21.25)	22.90 (20.70-25.17)	26.99 (25.13-28.88)	29.98 (26.14-33.23)	32.38 (29.06-35.89)	35.79 (33.79-37.31)
	Group L (n = 4)	22.08 (18.24-25.35)	25.17 (21.79-27.59)	27.21 (24.38-30.23)	29.72 (28.27-30.70)	31.89 (29.91-33.98)	32.22 (30.70-34.71)
F4	Group S (n = 3)	27.56 (23.40-28.34)	31.23 (26.84-32.22)	30.12 (27.89-32.12)	36.12 (32.39-36.34)	35.10 (34.12-36.27)	36.12 (34.06-37.28)
	Group L (n = 3)	23.98 (20.21-28.66)	29.12 (23.68-31.19)	32.00 (28.17-33.00)	29.00 (28.56-32.56)	33.43 (33.32-35.32)	35.30 (35.25-37.21)

POW: Postoperative weeks; Group S: Rabbits received splenectomy plus liver biopsy; Group L: Rabbits received liver biopsy only.

Table 7 Longitudinal changes in liver function between splenectomy and sham groups

		POW 0	POW 2	POW 4	POW 6	POW 8	POW 10
AST (IU/L)
F1	Group S (n = 5)	138.0 ± 87.3	236.7 ± 110.6	484.3 ± 244.2	307.3 ± 138.9	454.0 ± 291.3	574.3 ± 350.6
	Group L (n = 4)	447.0 ± 292.7	245.5 ± 98.3	589.5 ± 140.7	455.0 ± 309.7	517.5 ± 55.9	470.0 ± 155.6
F2	Group S (n = 4)	353.6 ± 208.4	473.4 ± 212.1	426.0 ± 186.4	448.6 ± 286.4	658.2 ± 221.9	575.6 ± 104.4
	Group L (n = 4)	392.0 ± 290.5	493.5 ± 269.0	407.5 ± 100.4	506.3 ± 156.8	494.5 ± 88.8	550.0 ± 125.6
F3	Group S (n = 4)	578.3 ± 219.5	681.3 ± 208.9	534.0 ± 292.2	622.7 ± 286.2	584.7 ± 144.5	713.3 ± 122.8
	Group L (n = 4)	598.8 ± 219.5	569.8 ± 208.9	651.5 ± 292.2	513.0 ± 286.2	435.5 ± 144.5	831.8 ± 122.8
F4	Group S (n = 3)	562.2 ± 356.6	604.2 ± 314.3	578.4 ± 247.7	623.8 ± 101.1	672.6 ± 122.6	525.6 ± 153.2
	Group L (n = 3)	412.6 ± 190.9	508.7 ± 253.8	604.0 ± 121.8	616.7 ± 203.1	571.0 ± 145.7	480.3 ± 91.4
ALT (IU/L)
F1	Group S (n = 5)	88.7 ± 39.2	270.3 ± 144.9	460.7 ± 227.5	379.0 ± 179.2	526.7 ± 185.8	440.7 ± 220.4
	Group L (n = 4)	195.0 ± 39.6	322.0 ± 76.4	430.5 ± 2.1	445.0 ± 108.9	560.5 ± 87.0	372.0 ± 198.0
F2	Group S (n = 4)	224.6 ± 187.8	240.8 ± 96.7	355.8 ± 165.8	342.6 ± 165.1	436.8 ± 74.9	458.0 ± 92.4
	Group L (n = 4)	291.8 ± 65.9	364.3 ± 86.5	310.3 ± 35.8	414.5 ± 136.8	473.3 ± 140.5	498.3 ± 174.0
F3	Group S (n = 4)	315.7 ± 232.7	434.0 ± 171.8	528.3 ± 137.7	588.0 ± 61.6	461.3 ± 208.2	497.3 ± 73.6
	Group L (n = 4)	477.8 ± 151.7	484.0 ± 34.4	459.3 ± 132.5	601.0 ± 274.9	488.8 ± 210.2	507.0 ± 133.2
F4	Group S (n = 3)	416.8 ± 286.2	490.6 ± 43.3	626.2 ± 93.0	478.0 ± 83.3	550.6 ± 252.5	519.2 ± 44.9
	Group L (n = 3)	529.0 ± 167.0	475.8 ± 106.7	600.4 ± 116.3	512.6 ± 207.8	576.8 ± 233.1	695.4 ± 150.6
Albumin (g/L)
F1	Group S (n = 5)	41.6 ± 2.4	40.5 ± 1.8	39.4 ± 2.3	40.5 ± 3.4	40.0 ± 2.0	39.8 ± 1.7
	Group L (n = 4)	41.3 ± 4.9	40.2 ± 3.0	40.3 ± 1.8	39.3 ± 0.6	39.3 ± 2.0	40.7 ± 1.3
F2	Group S (n = 4)	39.0 ± 1.9	38.3 ± 1.9	38.3 ± 1.5	38.9 ± 2.0	38.9 ± 1.6	38.9 ± 0.8
	Group L (n = 4)	39.6 ± 1.6	39.6 ± 1.7	38.0 ± 1.5	39.5 ± 0.8	39.0 ± 1.4	38.9 ± 1.9
F3	Group S (n = 4)	30.7 ± 4.3	30.3 ± 3.9	29.8 ± 3.3	31.0 ± 3.0	30.2 ± 3.8	30.5 ± 4.1
	Group L (n = 4)	31.1 ± 5.7	30.8 ± 5.1	31.8 ± 4.6	30.6 ± 5.2	30.9 ± 4.9	30.3 ± 4.2
F4	Group S (n = 3)	35.8 ± 5.6	36.0 ± 4.7	34.5 ± 4.1	34.2 ± 4.8	35.1 ± 5.1	35.5 ± 3.6
	Group L (n = 3)	35.3 ± 6.6	34.9 ± 5.8	35.4 ± 6.1	34.8 ± 3.4	34.8 ± 4.9	35.0 ± 5.6
TB (μmol/L)
F1	Group S (n = 5)	1.08 ± 0.10	1.30 ± 0.16	1.60 ± 0.16	1.58 ± 0.18	1.71 ± 0.23	1.70 ± 0.22
	Group L (n = 4)	1.34 ± 0.16	1.38 ± 0.08	1.39 ± 0.08	1.65 ± 0.20	1.51 ± 0.19	1.58 ± 0.25
F2	Group S (n = 4)	2.01 ± 0.72	2.35 ± 0.58	2.45 ± 0.61	2.65 ± 0.47	2.76 ± 0.51	2.81 ± 0.54
	Group L (n = 4)	2.08 ± 0.23	2.45 ± 0.51	2.62 ± 0.45	2.67 ± 0.23	2.99 ± 0.15	2.68 ± 0.40
F3	Group S (n = 4)	2.36 ± 0.64	2.52 ± 0.64	2.62 ± 0.51	2.66 ± 0.29	2.97 ± 0.19	3.09 ± 0.10
	Group L (n = 4)	2.59 ± 0.76	2.87 ± 0.42	2.88 ± 0.48	2.94 ± 0.33	3.13 ± 0.20	3.09 ± 0.12
F4	Group S (n = 3)	2.30 ± 0.56	2.58 ± 0.54	2.73 ± 0.22	2.88 ± 0.18	3.05 ± 0.26	3.03 ± 0.38
	Group L (n = 3)	2.35 ± 0.84	2.49 ± 0.52	2.82 ± 0.67	2.96 ± 0.13	3.11 ± 0.48	3.08 ± 0.51

POW: Postoperative weeks; Group S: Rabbits received splenectomy plus liver biopsy; Group L: Rabbits received liver biopsy only.